Recent, more stringent government regulation of diesel engine tailpipe emissions, have prompted development and application of various means to reduce these emissions. New diesel engine exhaust emissions regulations are focused on reducing diesel engine carbon particulate matter emissions (black soot). Of greatest concern are micron-sized carbon char particles, other particulate matter, and organic compounds which are adsorbed onto the surface of the carbon. A body of clear evidence now exists which links diesel particulate matter to a variety of serious respiratory illnesses including lung cancers and asthma. New environmental regulations worldwide are aimed at reducing particulate emissions from both new vehicles, and also existing vehicles already in use. Installing an exhaust gas treatment device to the engine's exhaust system is a common technique used to reduce particulate emissions. To this point, a highly efficient and cost effective device for diesel engines does not exist. Two devices currently in use are oxidation catalytic converters and particulate traps.